Physical interpretation of Reluctance

[cosmonova]

Hi,

I would like to know what is the physical interpretation of magnetic reluctance.
Also, I would like to know why should the magnetic flux in a magnetic circuit composed of different magnetic materials and subject to a magnetomotor force should be the same?

Thank you.

 

[Clausius2]

First of all, If you post your doubt in the Electrical Engineering forum, surely you will have better answers (more accurate).

Secondly, If there is some electrical engineer somewhere and I say something wrong, excuse me.

Thirdly, I'm going to try to remember my days of Electric Machines studies:

[tex] R=\frac{L}{S\mu}[/tex]

The Reluctance is the resistance showed by a Magnetic circuit to the pass of the magnetic flux.

L is the length of the magnetic path, the longer the path the greater the resistance. S is the cross section of the magnetic path, the wider the section the less the resistance. And [tex] \mu[/tex] is the magnetic permeability. Substances like Air of low permeability, makes greater the resistance (the gaps inside transformers and electric motors acts increasing the reluctance).

The physical interpretation is viewed better comparing the two similar laws:

[tex] F=Reluctance*\phi[/tex] where F=Electromotive Force; [tex] \phi[/tex]=magnetic flux. This is the Hopkins Law.

[tex] V=Resistance*I[/tex] Ohm's Law.

Both are similar but one is employed with electrical circuits and the other with magnetic circuts. The rest is left to your imagination .

 

[GSXR750]

The physical interpretation of magnetic reluctance is the measure of resistance that a material exhibits to the flow of magnetic flux. Similar to electrical resistance, magnetic reluctance is a property that determines the ease with which magnetic flux can pass through a material. It is dependent on the material's magnetic permeability, cross-sectional area, and length. A material with a higher reluctance will have a lower ability to conduct magnetic flux, while a material with a lower reluctance will have a higher ability to conduct magnetic flux.

As for the second question, the principle of magnetic circuit theory states that the total magnetic flux in a closed magnetic circuit must be conserved. This means that the sum of all the individual magnetic fluxes in the different materials making up the circuit must be equal to the magnetomotive force applied. This is similar to Kirchhoff's law in electrical circuits, where the sum of all currents entering and leaving a node must be equal. This principle ensures that the magnetic circuit is in equilibrium and the magnetic flux is distributed evenly throughout. Any imbalance in flux would result in a non-conservative circuit, which is not physically possible. Therefore, the magnetic flux in a magnetic circuit composed of different materials and subject to a magnetomotive force should be the same to maintain this principle of conservation.